| The dissertation have been mainly made on the tree traits,the observation of full bloom,fruit and nut traits,the nut setting rate of cross pollination, the fruit inclusion and branch traits of different Carya illinoensis clones at young,the research content and result as follows:(1) Six indexes of tree characteristics of 33 pecan (Carya illinoensis) clones were compared, and the correlation of them, tree classification and landscape application were analyzed. The results showed that there were highly significant differences among ground diameter,breast diameter,tree height, crown height and crown width within a clone or among clones. Clone 14,’Huangshan No.1’and clone 9 grow fast and could be popularized as excellent clones in the landscape. In the correlation analysis, there were highly significant correlation with the correlation indexes 0.92 and 0.96 between breast diameter and ground diameter, tree height and crown height. Tree form index, closed to the golden section point, was 0.59 to 0.82. The tree was spherical, broad-ovate and beautiful. C. illinoensis should be a very good species that could be as solitary appreciation tree, courtyard tree, street tree and mixed forest tree in the garden application.(2) Flowering phenology of thirty-two clones of Carya illinoensis was observed and compared. The results show that there exit some differences in flowering phenology from 2011 to 2014 and the duration of blossom process of all the thirty-two clones is from April 24 to May 21 in 2013.The lasting days of male flower of the thirty-two clones are 11-18d and the whole flowering period of female flower are 9-17 d in 2013. Days of receptivity stage of female flower and pollen shedding stage of male flower of thirty-two clones are all 3-8d. According to the time order of blossom of male and female flowers,sixteen clones could be determined to protogynous type. Ten clones protandrous type and six clones homogamy type; eighty-six feasible pollination combination could be selected according to the observation results. The best configuration scheme of clones is that the clones 1,5,17,27,29 and 35 as the pollinated varieties of clones Mahan,28 and 65.There is no significant differences for the length of male inflorescene among the thirty-two clones, but the differences among the clusters of male flower in a single branch, the number of pollen sac in a single male inflorescence,the total number of male inflorescence per plant, numbers of female flower per branch, numbers of male inflorescen per cluster and numbers of female flower per plant reached a significant level. There is a biggest range of whole variation in the total number of male inflorescene per plant, the coefficient of variation is 75.51%.(3) Fruit characters, nut traits and yield of 33 pecan (Carya illinoensis) clones were compared, and the correlation and System Cluster of 12 indexes between them was analyzed. The result showed highly significant difference among the clones in the 12 indexes studied. The CV (coefficient of variance) of the fruit characters appeared in the order of fresh fruit yield per tree> fruit weight> peel thickness> fruit height> fruit shape index >fruit diameter, being 85.78%,12.05%,11.29%, 6.34%,5.74% and 5.31%, respectively. A similar order was observed for the nut traits, nut yield per tree> nut weight> nut weight in fruit> nut height> nut shape index> nut diameter. Fruit weight was in a significant positive correlation with nut weight in 33 clones, and fruit height was in a highly significant positive correlation with nut height, Fruit diameter was in a significant positive correlation with nut diameter, the nut size can be determined by the size of the fresh fruit.The clones that clustered,the 12 indexes of which measured are more closer, that the difference of them is not significant,on the contrary, significant.(4) The crossing nut setting and its characters of different carya illinoensis clones were compared among different crossing combinations. The results showed that the nuts set much more from pollination to June 25, from June 25 to July 15, although the nuts set, but the nuts setting curves begin to flatten, after July 15, the nuts setting curves begin to more flatter with less nuts set.In terms of the nut setting of different crossing combination, the clone No.35 can be the best pollination clone as the clone No.28 and No.65, respectively with the nuts setting rate 47.15%and 14.59%when harvested, the clone No.5 can be the best pollination clone as Mahan with the nuts setting rate 21.16%.Mahan was the pollination clone suitable for clone No.11 and Huangshan No.l was suitable for No.21.To the characters of crossing nuts,the traits of these crossing combination that ♂28×♂65×♂35 and ♂ Mahan×♂ 29 were the best.When middle nut No.21 was female parent, its crossing nuts had significant pollen texture effects. The crossing nut increased when large nut Mahan as its male parent and it decreased when small nut Huangshan No.1 as its pollination clone.(5) In order to filter out clones with its excellent nut traits on economy and quality for more low-yielding pecan forest,poor nut quality and low economic benefits. The nut economy and quality characters of 27 Carya illinoensis clones were compared by the methods of sampling, measurement and analysis.The results showed that the seed rate of fresh fruit of the clone No.19 was higher than others, and the water content of air dried was lower, kernel percent of dried air clones No.1, No.34, No.28 was much higher, four clones can be promoted as the excellent economic characters. The CV (coefficient of variation) were less than 20% of fat,protein and soluble sugar percent,and the relative amount of fatty acid,relatively stable. The clones No.28 and No.17 can be as the excellent clones because of its higher unsaturated fatty acid and lower saturated fatty acid, the UFA was respectively 92.43% and 92.33%and the SFA only 7.26%and 7.46%.Kenerl percent and water content of kernel of air dried were significantly negatively correlated with the correlation index -0.67**.The unsaturated fatty acid,oleic acid and Linoleic acid showed a significant negative correlation with the correlation index -0.98**,and the total content kept almost the same of oleic and linoleic acid,that is, the unsaturated fatty acid in nut is relatively stable. The comprehensive analysis of nut quality showed that the clones No.1, No.7, No.8, No.12, No.19, No.23 and No.26 can also be planted as the main cultivars with Mahan.(5)There exist some differences of fruiting rate and fruiting branches among 15 clones, fruiting rate of most clones is above 80.00%and the clone No.28 reached the highest 90.67%. The results are different between canopy level and branches long or thick among 15 clones.In the upper, middle or lower canopy, clone 9 and 65, the numbers of fruiting branches were higher than those in canopy level among 15 clones,followed by clone No.11,23,28, and the fewer wih the clone No.32.The nut setting rate of clone No 42 in July and August was higher than other clones respectively with 70.33% and 59.69%. On the aspect of numbers of sprouted fruit branch per parent branch, fruiting branches of clone No.65,No.48,Mahan and No.48 than the other clones’. There was a significant negative correlation between Sprouting ability and nut setting rate with correlation index -0.70**, that was the more fruiting numbers per last-year-grown branch. There was significantly positive correlation between numbers of sprouted fruit branch of per parent branch and the numbers of female flowers with correlation index 1.00**, Numbers of sprouted fruit branch of per parent branch can be get by the numbers of female flowers. |
PDF Full Text Request